In reactors containing a large amount of catalyst, it becomes necessary to remove the catalyst from the reactor upon degradation of the catalyst. Sampling tubes are sometimes inserted into the reactor to sense the degradation or performance level of the catalyst material. In such environments, the commonly used slide valve is rendered inoperable due to the presence of the sampling tube extending from the reactor nozzle. It becomes necessary to provide a valve which can be selectively installed to the reactor nozzle prior to when the sampling tube is to be removed. After installation of the valve, the sampling tube can be removed and the valve closed to prevent loss of the catalyst material.
A patentability search was conducted on the invention and the following patents were uncovered:
______________________________________ INVENTOR U.S. PAT. NO. DATE ______________________________________ Levi Lincoln RE 105 Jan. 25, 1848 John Marchbank 73,822 Jan. 28, 1868 N. W. Krouse 533,175 Jan. 29, 1895 J. T. Perkins 600,444 March 8, 1898 J. C. Perry 606,025 June 21, 1898 W. S. Robertson 867,303 October 1, 1907 J. Artese 1,480,141 Jan. 8, 1924 B. F. Remington 1,938,224 Dec. 5, 1933 W. L. Walker 2,174,100 Sept. 26, 1939 R. D. Poulsen 3,521,665 July 28, 1970 ______________________________________
The 1898 patent issued to Perry for a water faucet valve includes a pivotal plate for selectively engaging enveloping flanges to open and close a passageway carrying water.
The 1868 patent issued to Marchbank sets forth a pivotal valve having an extending handle thereon for selectively opening and closing the gate through a transverse bar. The 1848 patent issued to Lincoln also sets forth a pivotal gate having an extended handle disposed between two plates.
The 1907 patent issued to Robertson shows a gate being pivoted at one end and having a pre-formed circular gate with an outwardly extending handle at the other end. The 1970 patent issued to Poulsen discloses a gate valve circular in shape for use in irrigation systems and the 1939 patent issued to Walker sets forth an oil sampler utilizing a pivotal gate.
The 1924 patent issued to Artese discloses a pivotal gate having the pivot in the middle with an extending handle portion. The Artese pivotal gate is utilized for water distribution and regulation thereof. The 1933 patent issued to Remington et al also utilizes a pivotal gate to obtain a water sample. The 1898 patent issued to Perkins shows a pipe coupling utilizing a pivotal gate for selectively opening and closing a passageway. Finally, the 1895 patent issued to Krouse also shows a pivotal valve for selectively closing an opening.
However, none of the prior art references set forth the pivotal retrofittable valve of the present invention having formed open regions for removal of any material carried in the passageway which could clog or jam the valve and having an arcuate segmented portion on the pivotal valve to provide a full and complete seal around the passageway as presented in the next section.